51299314 ÷ 420 
The aim is to understand the frequency of 420 in 51299314.

Let's proceed to step 1:
When dividing 5 by 420, we get 0 with a remainder of 5.
Write down 0 as next digit of the result. 
Result so far: 0.0
The remainder is 5 after subtracting 0 from 5.
Take the next digit (1) from the dividend and append it to 5, then repeat: 51 / 420

Going ahead to step 2:
The number 420 fits into 51 0 times, leaving a remainder of 51.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtracting 0 from 51 leaves us with 51.
Include the next digit (2) from the dividend after 51, then repeat: 512 / 420

Let's proceed to step 3:
When dividing 512 by 420, we get 1 with a remainder of 92.
The next digit of our result is 1. 
Result so far: 1.0
The remainder is 92 after subtracting 420 from 512.
Fetch the next digit (9) from the dividend, attach it to 92 and continue: 929 / 420

Going ahead to step 4:
The number 420 fits into 929 2 times, leaving a remainder of 89.
The number 2 becomes the next digit in our result. 
Result so far: 12.0
The remainder is 89 after subtracting 840 from 929.
Append the next digit (9) from the dividend to 89 and continue with: 899 / 420

Going ahead to step 5:
899 divided by 420 is 2 with a remainder of 59.
The next digit of our result is 2. 
Result so far: 122.0
Subtract 840 from 899 to get 59.
Take the next digit (3) from the dividend and append it to 59, then repeat: 593 / 420

Moving on to step 6:
When dividing 593 by 420, we get 1 with a remainder of 173.
Write down 1 as next digit of the result. 
Result so far: 1221.0
Deduct 420 from 593 and we're left with 173.
Include the next digit (1) from the dividend after 173, then repeat: 1731 / 420

Moving on to step 7:
If we divide 1731 by 420, we get 4 and a remainder of 51.
Write down 4 as next digit of the result. 
Result so far: 12214.0
The remainder is 51 after subtracting 1680 from 1731.
Grab the next digit (4) from the dividend, add it to 51, then carry on: 514 / 420

On to step 8:
420 goes into 514 1 times with a remainder of 94.
Use 1 as the next digit of our solution. 
Result so far: 122141.0
If we take 420 away from 514, we end up with 94.
Since there are no more digits in the dividend, we add a zero to the remainder making it 940, and continue the process.

Let's proceed to step 9:
420 goes into 940 2 times with a remainder of 100.
The next digit of our result is 2. 
Result so far: 122141.2
Subtracting 840 from 940 leaves us with 100.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1000, and continue the process.

Going ahead to step 10:
420 goes into 1000 2 times with a remainder of 160.
The next digit of our result is 2. 
Result so far: 122141.22
If we subtract 840 from 1000, we get 160.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1600, and continue the process.

After the division, we end up with 122141.22 and a remainder of 0.16.